Onychomycosis (“OM”) is a fungal infection of toenails or fingernails. The infection may encompass any component of the nail, including the nail bed, nail plate, or nail matrix. OM can become very unsightly and may produce pain, discomfort, and disfigurement, all of which can lead to physical and occupational limitations. A disorder such as OM may have a detrimental effect on an individual's quality of life, affecting his psychosocial and emotional well-being. The main subtypes of OM are distal lateral subungual OM (“DLSO”), white superficial OM (“WSO”), proximal subungual OM (“PSO”), endonyx OM (“EO”), and candidal OM. Patients may have a combination of these subtypes. Total dystrophic OM refers to the most advanced form of any subtype. The onset of fungal infection is caused by three main classes of fungi: dermatophytes, yeasts, and nondermatophyte molds. The most common cause of OM worldwide is due to the infection of dermatophytes, including the genera Epidermophyton, Microsporum, and Trichophyton. There are two major pathogens that account for a majority of OM cases, Trichophyton rubrum and Trichophyton mentagrophytes. 
There are several treatment options for clinicians, including systemic or topical antifungal medications and natural remedies. However, the rate of success remains low, the rate of recurrence remains high, and the costs and risks involved may be steep for some patients. For example, the most effective accepted treatments are prescription oral pharmaceuticals that have significant negative side effects, such as skin rash and liver damage. An effective alternative to pharmacological solutions is needed that is safe for the patient and prevents recurrence of the infection.
Low level laser therapy (“LLLT”) is used in the treatment of a broad range of conditions. LLLT improves wound healing, reduces edema, and relieves pain of various etiologies, including successful application to wound and surgical sites to reduce inflammation and pain. LLLT is also used in the treatment and repair of injured muscles and tendons. LLLT utilizes low level laser energy, wherein the treatment has a dose rate that causes no immediate detectable temperature rise of the treated tissue and no macroscopically visible changes in tissue structure. Consequently, the treated and surrounding tissue is not heated or damaged, and the patient feels no sensation during treatment. Some LLLT applications have effectively photodestroyed a targeted biological element under suitable treatment conditions. For example, LLLT may be used in fat reduction to create a transition pore in fat cell walls, through which fat is released into the interstitial space.
There are a number of variables in laser therapy, including the wavelength of the laser beam, the area impinged by the laser beam, the shape of the beam spot when it impinges the area, the power of the laser source, the intensity or fluence of the laser energy, the laser pulse width, and the treatment duration. These variables typically depend heavily on the tissue characteristics of the specific patient, and the success of each therapy depends on the relationship and combination of these variables. For example, fat reduction may be facilitated with one regimen utilizing a given power, wavelength, and treatment duration, whereas pain may be treated with a regimen utilizing a different wavelength and treatment duration, and inflammation a third regimen. Specific devices may be used for each type of therapy.
Therefore, an object of this invention is to provide laser therapy devices and methods of using the devices to treat OM and other fungal infections of the fingernails or toenails. A further object of the invention is to incite photodestruction of fungal bacteria without adversely affecting surrounding healthy tissue. It is another object of this invention to destroy fungal bacteria using laser light in multiple different pulse widths. It is a particular object of this invention to provide methods of using a compact, standalone laser device to provide low level laser therapy which can be used to treat OM and other fungal infections. It is another particular object of this invention to provide methods of using a hand-held therapeutic laser device to provide low level laser therapy which can be used to treat OM and other fungal infections.